You make two scarves and join them with the hood stitches. Those are the 48 stitches that you'll cast on to join them. 26 + 48 + 26 = 100 stitches total.
With any pattern that looks complicated, I suggest that you just forge on, line by line. Don't look too far ahead. It's kind of like looking at page 8 of the directions for building a bicycle. "Fit flange B into slot C."--until you have flange B and slot C in front of you, it makes no sense. Very often with knitting, until you have the piece in front of you, it's impossible to visualize how it will all come together.
"Trust the pattern!"
Time flies like an arrow, but fruit flies like a banana.
Hop aboard while we follow the cloud-covered van of knitting harmony, man!! Woooo!! --Hedgehog
IngridKH on Ravelry